According to the Economist:

“One of Nokia’s in-house anthropologists, Jan Chipchase, recently investigated how people carry their phones, for example. He and his colleagues carried out street-level surveys in 11 cities on four continents. They found that 60% of men carried their phones in their trouser pockets, whereas 61% of women carried their phones in handbags. (The difficulty of finding a mobile phone in a cluttered handbag meant that half of women reported missing calls as a result.)”